Plotting Date Ranges
The release, 1.9.31.x
added the capability to make partial plots.
-
Either with indices to the full length array of timestamps kept in strategy instances
-
Or with actual
datetime.date
ordatetime.datetime
instances that limit what has to be plotted.
Everything still over the standard cerebro.plot
. Example:
cerebro.plot(start=datetime.date(2005, 7, 1), end=datetime.date(2006, 1, 31))
Being that the straightforward way to do it for humans. Humans with extended
capabilities can actually try indices to the datetime
timestamps as in:
cerebro.plot(start=75, end=185)
A very standard sample containing a Simple Moving Average (on-data
plotting), a Stochastic (independent plotting) and a CrossOver of the
Stochastic lines is presented below. The arguments to cerebro.plot
are
passed as command line arguments.
An execution with the date
approach:
./partial-plot.py --plot 'start=datetime.date(2005, 7, 1),end=datetime.date(2006, 1, 31)'
The eval
magic in python allows to directly write datetime.date
in the
command line and map actually that to something sensible. The output chart
Let’s compare it with the full plot to see that data was actually skipped from both ends:
./partial-plot.py --plot
The eval
magic in python allows to directly write datetime.date
in the
command line and map actually that to something sensible. The output chart
Sample Usage
$ ./partial-plot.py --help
usage: partial-plot.py [-h] [--data0 DATA0] [--fromdate FROMDATE]
[--todate TODATE] [--cerebro kwargs] [--broker kwargs]
[--sizer kwargs] [--strat kwargs] [--plot [kwargs]]
Sample for partial plotting
optional arguments:
-h, --help show this help message and exit
--data0 DATA0 Data to read in (default:
../../datas/2005-2006-day-001.txt)
--fromdate FROMDATE Date[time] in YYYY-MM-DD[THH:MM:SS] format (default: )
--todate TODATE Date[time] in YYYY-MM-DD[THH:MM:SS] format (default: )
--cerebro kwargs kwargs in key=value format (default: )
--broker kwargs kwargs in key=value format (default: )
--sizer kwargs kwargs in key=value format (default: )
--strat kwargs kwargs in key=value format (default: )
--plot [kwargs] kwargs in key=value format (default: )
Sample Code
from __future__ import (absolute_import, division, print_function,
unicode_literals)
import argparse
import datetime
import backtrader as bt
class St(bt.Strategy):
params = (
)
def __init__(self):
bt.ind.SMA()
stoc = bt.ind.Stochastic()
bt.ind.CrossOver(stoc.lines.percK, stoc.lines.percD)
def next(self):
pass
def runstrat(args=None):
args = parse_args(args)
cerebro = bt.Cerebro()
# Data feed kwargs
kwargs = dict()
# Parse from/to-date
dtfmt, tmfmt = '%Y-%m-%d', 'T%H:%M:%S'
for a, d in ((getattr(args, x), x) for x in ['fromdate', 'todate']):
if a:
strpfmt = dtfmt + tmfmt * ('T' in a)
kwargs[d] = datetime.datetime.strptime(a, strpfmt)
# Data feed
data0 = bt.feeds.BacktraderCSVData(dataname=args.data0, **kwargs)
cerebro.adddata(data0)
# Broker
cerebro.broker = bt.brokers.BackBroker(**eval('dict(' + args.broker + ')'))
# Sizer
cerebro.addsizer(bt.sizers.FixedSize, **eval('dict(' + args.sizer + ')'))
# Strategy
cerebro.addstrategy(St, **eval('dict(' + args.strat + ')'))
# Execute
cerebro.run(**eval('dict(' + args.cerebro + ')'))
if args.plot: # Plot if requested to
cerebro.plot(**eval('dict(' + args.plot + ')'))
def parse_args(pargs=None):
parser = argparse.ArgumentParser(
formatter_class=argparse.ArgumentDefaultsHelpFormatter,
description=(
'Sample for partial plotting'
)
)
parser.add_argument('--data0', default='../../datas/2005-2006-day-001.txt',
required=False, help='Data to read in')
# Defaults for dates
parser.add_argument('--fromdate', required=False, default='',
help='Date[time] in YYYY-MM-DD[THH:MM:SS] format')
parser.add_argument('--todate', required=False, default='',
help='Date[time] in YYYY-MM-DD[THH:MM:SS] format')
parser.add_argument('--cerebro', required=False, default='',
metavar='kwargs', help='kwargs in key=value format')
parser.add_argument('--broker', required=False, default='',
metavar='kwargs', help='kwargs in key=value format')
parser.add_argument('--sizer', required=False, default='',
metavar='kwargs', help='kwargs in key=value format')
parser.add_argument('--strat', required=False, default='',
metavar='kwargs', help='kwargs in key=value format')
parser.add_argument('--plot', required=False, default='',
nargs='?', const='{}',
metavar='kwargs', help='kwargs in key=value format')
return parser.parse_args(pargs)
if __name__ == '__main__':
runstrat()